WO2012098840A1

WO2012098840A1 - Resin composition and molded article including same

Info

Publication number: WO2012098840A1
Application number: PCT/JP2012/000162
Authority: WO
Inventors: 宏枝熊澤; 洋揮山崎; 鈴木　英昭; 興造田村
Original assignee: 株式会社クラレ
Priority date: 2011-01-17
Filing date: 2012-01-12
Publication date: 2012-07-26
Also published as: EP2666823B1; US20130295308A1; EP2666823A4; CN103328574A; MX2013008263A; CN103328574B; KR101863740B1; JPWO2012098840A1; JP5981852B2; US10090077B2; EP2666823A1; MX348171B; KR20140007845A; ES2626607T3

Abstract

The present invention provides a polyamide resin composition which has an adequate melt viscosity although an electrically conductive filler is contained therein and which has excellent moldability and is excellent in terms of electrical conductivity, low-temperature impact resistance, and fuel-barrier properties. This polyamide resin composition comprises a polyamide that comprises dicarboxylic acid units, 50 mol% or more of which are accounted for by terephthalic acid units and/or naphthalenedicarboxylic acid units, and diamine units, 60 mol% or more of which are accounted for by units of a C_4-18 aliphatic diamine, and that has a terminal-amino-group content of 5-60 µmol/g, a resin modified with an unsaturated compound having a carboxy group and/or an acid anhydride group, and an electrically conductive filler in specific amounts. In the composition, the difference between the number of moles (M_I) of the terminal amino groups of the polyamide and the number of moles (M_II) of the carboxy groups and acid anhydride groups of the modified resin, per g of the sum of the polyamide and the modified resin, is -5.0 µmol or greater but less than 4.0 µmol and M_II is greater than 4.0 µmol.

Description

Resin composition and molded article containing the same

The present invention relates to a conductive polyamide resin composition excellent in conductivity, low-temperature impact resistance, fuel barrier property, and moldability, and a molded article containing the same.

Generally, resin is an electrically insulating material, but in many applications, electrical conductivity is required in applications such as members for electric and electronic parts and parts for automobile parts. Examples of the member for automobile parts include a fuel pipe and a fuel tank. Since these members generate static electricity due to friction during the transportation of fuel, it is essential to provide conductivity in order to remove the static electricity.

In recent years, components such as automobile fuel pipes and fuel tanks have high heat resistance, high impact resistance (especially at low temperatures), high fuel barrier properties, and good moldability in addition to conductivity. Is required.

As the means for imparting conductivity to the resin, for example, a method of adding a conductive filler such as carbon black to the resin is the most common. Polyamide resins are used in automobile fuel pipes and fuel tanks because of their excellent heat resistance and other properties, and it is known that conductive polyamide resins can be obtained by mixing carbon black with polyamide resins. (For example, refer to Patent Document 1).

JP 2008-179753 A

However, when carbon black is blended with the polyamide resin, there is a problem that moldability is lowered due to an increase in the melt viscosity of the polyamide resin. Accordingly, the present invention provides a conductive polyamide resin composition that contains a conductive filler, has an appropriate melt viscosity, is excellent in moldability, and is excellent in conductivity, low-temperature impact resistance, and fuel barrier properties. It aims at providing the molded article containing this.

As a result of intensive studies to solve the above-described problems of the prior art, the present inventors have found that a semi-aromatic polyamide having a specific terminal amino group content, an unsaturated group having a carboxyl group and / or an acid anhydride group. In a polyamide resin composition containing a modified resin modified with a compound and a conductive filler, the number of moles of terminal amino groups of the polyamide used, and the number of moles of carboxyl groups and acid anhydride groups of the modified resin, The inventors have found that the above-described problems can be solved by setting the specific range, and have completed the present invention.

That is, the present invention comprises a dicarboxylic acid unit containing 50 to 100 mol% of terephthalic acid units and / or naphthalenedicarboxylic acid units, and a diamine unit containing 60 to 100 mol% of aliphatic diamine units having 4 to 18 carbon atoms. A polyamide (A) having a terminal amino group content ([NH ₂ ]) of 5 to 60 μmol / g,
A polyamide resin composition containing a modified resin (B) modified with an unsaturated compound having a carboxyl group and / or an acid anhydride group, and a conductive filler (C),
40 to 96.5 parts by mass of the polyamide (A) and the modified resin (B) with respect to 100 parts by mass in total of the polyamide (A), the modified resin (B), and the conductive filler (C). 3 to 30 parts by mass, 0.5 to 30 parts by mass of the conductive filler (C), and the terminal amino group of the polyamide (A) in a total of 1 g of the polyamide (A) and the modified resin (B) the number of moles and (M _I), the modified resin (B) the number of moles of carboxyl groups and acid anhydride groups of the difference between the _{_{(M II) (M I -M}} II) is, -5.0Myu mol 4 less than .0μ mol, and an M _II is greater polyamide resin composition than 4.0μ mol.

The present invention is also a molded article containing the polyamide resin composition described above.

The present invention is also a fuel pipe including a layer containing the polyamide resin composition.

According to the present invention, there is provided a conductive polyamide resin composition having an appropriate melt viscosity, containing a conductive filler, excellent moldability, and having excellent conductivity, low-temperature impact resistance, and fuel barrier properties. Is done. Molded articles containing the conductive polyamide resin composition are useful for various applications, and are particularly suitable for fuel piping.

The polyamide resin composition of the present invention contains a dicarboxylic acid unit containing 50 to 100 mol% of terephthalic acid units and / or naphthalenedicarboxylic acid units and 60 to 100 mol% of aliphatic diamine units having 4 to 18 carbon atoms. Modified resin modified with an unsaturated compound having a diamine unit and a terminal amino group content ([NH ₂ ]) of 5 to 60 μmol / g, a carboxyl group and / or an acid anhydride group (B) and a conductive filler (C) are contained.

The dicarboxylic acid unit constituting the polyamide (A) contains 50 to 100 mol% of terephthalic acid units and / or naphthalenedicarboxylic acid units. When the content of the terephthalic acid unit and / or naphthalenedicarboxylic acid unit in the dicarboxylic acid unit is less than 50 mol%, the heat resistance and fuel barrier properties of the obtained polyamide resin composition are lowered. The content of the terephthalic acid unit and / or naphthalenedicarboxylic acid unit in the dicarboxylic acid unit is preferably in the range of 75 to 100 mol%, and more preferably in the range of 90 to 100 mol%.

The dicarboxylic acid unit constituting the polyamide (A) may contain other dicarboxylic acid units other than the terephthalic acid unit and / or the naphthalenedicarboxylic acid unit within a range not impairing the effects of the present invention as long as it is 50 mol% or less. Good. Examples of such other carboxylic acid units include malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethylglutaric acid, 2, Aliphatic dicarboxylic acids such as 2-diethylsuccinic acid, azelaic acid, sebacic acid and suberic acid; alicyclic dicarboxylic acids such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid; isophthalic acid, 2, 6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3-phenylenedioxydiacetic acid, diphenic acid, diphenylmethane-4,4 '-Dicarboxylic acid, diphenylsulfone-4,4'-dicarboxylic acid, 4,4'-biphenyldi Can be mentioned units derived from an aromatic dicarboxylic acid such as carboxylic acids, it can include one or more of them. The content of these other dicarboxylic acid units in the dicarboxylic acid unit is preferably 25 mol% or less, and more preferably 10 mol% or less. Furthermore, a unit derived from a polyvalent carboxylic acid such as trimellitic acid, trimesic acid, pyromellitic acid, and the like may be included within a range in which melt molding is possible.

The diamine unit constituting the polyamide (A) contains 60 to 100 mol% of an aliphatic diamine unit having 4 to 18 carbon atoms. When the polyamide (A) containing an aliphatic diamine unit having 4 to 18 carbon atoms in this proportion is used, a polyamide resin composition excellent in toughness, slidability, heat resistance, moldability, low water absorption, and lightness can be obtained. can get. The content of the aliphatic diamine unit having 4 to 18 carbon atoms in the diamine unit is preferably in the range of 75 to 100 mol%, and more preferably in the range of 90 to 100 mol%.

Examples of the aliphatic diamine unit having 4 to 18 carbon atoms include 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,7-heptanediamine, and 1,8-octane. Diamine, 1,9-nonanediamine, 1,10-decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine, 1,13-tridecanediamine, 1,14-tetradecanediamine, 1,15-pentadecanediamine Linear aliphatic diamines such as 1,16-hexadecanediamine, 1,17-heptadecanediamine, 1,18-octadecanediamine; 2-methyl-1,3-propanediamine, 2-methyl-1,4- Butanediamine, 2-methyl-1,5-pentanediamine, 3-methyl-1,5-pentanediamine, 2,2 Branched chains such as 4-trimethyl-1,6-hexanediamine, 2,4,4-trimethyl-1,6-hexanediamine, 2-methyl-1,8-octanediamine, 5-methyl-1,9-nonanediamine The unit derived from an aliphatic diamine or the like can be exemplified, and one or more of these can be contained.

The aliphatic diamine unit having 4 to 18 carbon atoms is preferably an aliphatic diamine unit having 6 to 18 carbon atoms, and a polyamide resin composition that is more excellent in heat resistance, low water absorption and chemical resistance can be obtained. Therefore, 1,9-nonanediamine units and / or 2-methyl-1,8-octanediamine units are more preferable. When the diamine unit includes both a 1,9-nonanediamine unit and a 2-methyl-1,8-octanediamine unit, the molar ratio of the 1,9-nonanediamine unit to the 2-methyl-1,8-octanediamine unit is 1,9-nonanediamine unit / 2-methyl-1,8-octanediamine unit = preferably in the range of 95/5 to 40/60, more preferably in the range of 80/20 to 50/50. .

The diamine unit constituting the polyamide (A) may contain other diamine units other than the aliphatic diamine unit having 4 to 18 carbon atoms as long as it is 40 mol% or less. Examples of such other diamine units include aliphatic diamines such as ethylenediamine, 1,2-propanediamine, and 1,3-propanediamine; alicyclic diamines such as cyclohexanediamine, methylcyclohexanediamine, and isophoronediamine; p-phenylene. Examples include units derived from aromatic diamines such as diamine, m-phenylenediamine, xylylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylsulfone, and 4,4′-diaminodiphenyl ether. And one or more of these may be included. The content of these other diamine units in the diamine unit is preferably 25 mol% or less, and more preferably 10 mol% or less.

The polyamide (A) may contain an aminocarboxylic acid unit as long as the effects of the present invention are not impaired. Examples of the aminocarboxylic acid unit include units derived from 11-aminoundecanoic acid, 12-aminododecanoic acid and the like, and two or more aminocarboxylic acid units may be included. The content of aminocarboxylic acid units in the polyamide (A) is preferably 40 mol% or less, more preferably 20 mol% or less, based on 100 mol% of all monomer units constituting the polyamide (A). Preferably, it is 10 mol% or less.

The polyamide (A) may contain a lactam unit as long as the effects of the present invention are not impaired. Examples of the lactam unit include units derived from caprolactam, lauryl lactam, and the like, and two or more lactam units may be included. The content of lactam units in the polyamide (A) is preferably 40 mol% or less, more preferably 20 mol% or less, with respect to 100 mol% of all monomer units constituting the polyamide (A). More preferably, it is 10 mol% or less.

In the polyamide (A), it is preferable that 10% or more of the end groups of the molecular chain are sealed with an end-capping agent. The ratio of the end groups of the molecular chain being sealed with the end-capping agent (end-capping rate) is more preferably 20% or more. When a polyamide (A) having a terminal blocking rate of 10% or more is used, a polyamide resin composition having more excellent physical properties such as melt stability and hot water resistance can be obtained.

The end capping agent is not particularly limited as long as it is a monofunctional compound having reactivity with the amino group or carboxyl group at the end of the polyamide, but from the viewpoint of reactivity and stability of the capping end, Carboxylic acid or monoamine is preferable, and monocarboxylic acid is more preferable from the viewpoint of easy handling. In addition, acid anhydrides, monoisocyanates, monoacid halides, monoesters, monoalcohols, and the like can also be used as the end-capping agent.

The monocarboxylic acid used as the end-capping agent is not particularly limited as long as it has reactivity with an amino group. For example, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, laurin Aliphatic monocarboxylic acids such as acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid, pivalic acid and isobutyric acid; cycloaliphatic monocarboxylic acids such as cyclohexanecarboxylic acid; benzoic acid, toluic acid, α-naphthalenecarboxylic acid , Β-naphthalene carboxylic acid, methyl naphthalene carboxylic acid, aromatic monocarboxylic acid such as phenyl acetic acid; any mixtures thereof. Among these, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearin, etc. Acid and benzoic acid are preferred.

The monoamine used as the end-capping agent is not particularly limited as long as it has reactivity with a carboxyl group. For example, methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearyl Aliphatic monoamines such as amine, dimethylamine, diethylamine, dipropylamine and dibutylamine; Cycloaliphatic monoamines such as cyclohexylamine and dicyclohexylamine; Aromatic monoamines such as aniline, toluidine, diphenylamine and naphthylamine; any mixtures thereof Can be mentioned. Among these, butylamine, hexylamine, octylamine, decylamine, stearylamine, cyclohexylamine, and aniline are preferable from the viewpoints of reactivity, boiling point, stability of the sealing end, price, and the like.

The end-capping rate of the polyamide (A) was determined by measuring the number of carboxyl groups, amino groups, and end groups blocked by the end-capping agent present in the polyamide (A). It is obtained according to 1). The number of each terminal group is preferably determined from the integral value of the characteristic signal corresponding to each terminal group by ¹ H-NMR in terms of accuracy and simplicity.
Terminal sealing rate (%) = [(TS) / T] × 100 (1)
[Wherein T represents the total number of end groups of the molecular chain of the polyamide (A) (this is usually equal to twice the number of polyamide molecules), and S represents the remaining carboxyl group ends and amino Represents the total number of base ends. ]

Polyamide (A) can be produced using any method known as a method for producing polyamide. For example, it can be produced by a solution polymerization method or interfacial polymerization method using acid chloride and diamine as raw materials, a melt polymerization method using dicarboxylic acid and diamine as raw materials, a solid phase polymerization method, a melt extrusion polymerization method, or the like.

When producing the polyamide (A), in addition to the above-mentioned end-capping agent, for example, phosphoric acid, phosphorous acid, hypophosphorous acid, their salts or esters can be added as a catalyst. Examples of the salt or ester include phosphoric acid, phosphorous acid or hypophosphorous acid, potassium, sodium, magnesium, vanadium, calcium, zinc, cobalt, manganese, tin, tungsten, germanium, titanium, antimony, and the like. Salt with metal; ammonium salt of phosphoric acid, phosphorous acid or hypophosphorous acid; ethyl ester, isopropyl ester, butyl ester, hexyl ester, isodecyl ester, decyl of phosphoric acid, phosphorous acid or hypophosphorous acid Examples thereof include esters, stearyl esters, and phenyl esters.

The polyamide (A) preferably has an intrinsic viscosity [η] measured in concentrated sulfuric acid at 30 ° C. in the range of 0.6 to 2.0 dl / g, and 0.7 to 1.9 dl / g. More preferably, it is in the range of g, more preferably in the range of 0.8 to 1.8 dl / g. If a polyamide (A) having an intrinsic viscosity of less than 0.6 dl / g is used, the mechanical properties of the resulting polyamide resin composition tend to be lowered, and a polyamide (A) having an intrinsic viscosity of more than 2.0 dl / g If used, the fluidity of the resulting polyamide resin composition tends to decrease and the moldability tends to deteriorate.

The polyamide (A) has a terminal amino group content ([NH ₂ ]) of 5 to 60 μmol / g, preferably in the range of 5 to 50 μmol / g, and in the range of 5 to 30 μmol / g. More preferably, it is within. When the terminal amino group content ([NH ₂ ]) is less than 5 μmol / g, the compatibility between the polyamide and the modified resin (B) is insufficient, and when the terminal amino group content is greater than 60 μmol / g. In this case, the conductivity, the long-term heat resistance, and the weld strength are reduced.

The polyamide (A) having a terminal amino group content ([NH ₂ ]) in the above range can be produced, for example, as follows.

First, a dicarboxylic acid, a diamine, and optionally an aminocarboxylic acid, a lactam, a catalyst, and a terminal blocking agent are mixed to produce a nylon salt. At this time, the number of moles (X) of all carboxyl groups and the number of moles (Y) of all amino groups contained in the reaction raw material are represented by the following formula (2).
−0.5 ≦ [(Y−X) / Y] × 100 ≦ 2.0 (2)
Is satisfied, it is easy to produce a polyamide (A) having a terminal amino group content ([NH ₂ ]) of 5 to 60 μmol / g, which is preferable. Next, the produced nylon salt is heated to a temperature of 200 to 250 ° C. to obtain a prepolymer having an intrinsic viscosity [η] at 30 ° C. in concentrated sulfuric acid of 0.10 to 0.60 dl / g, and the degree of polymerization is further increased. Thus, the polyamide (A) used in the present invention can be obtained. When the intrinsic viscosity [η] of the prepolymer is in the range of 0.10 to 0.60 dl / g, there is little shift in the molar balance of carboxyl groups and amino groups and a decrease in polymerization rate at the stage of increasing the degree of polymerization. Furthermore, polyamide (A) excellent in various performance and moldability with a small molecular weight distribution can be obtained. When the polymerization degree is increased by the solid phase polymerization method, it is preferably performed under reduced pressure or under an inert gas flow. When the polymerization temperature is in the range of 200 to 280 ° C., the polymerization rate is high and the productivity is increased. And can effectively suppress coloring and gelation. Further, when the polymerization degree is increased by a melt extruder, the polymerization temperature is preferably 370 ° C. or less. When polymerization is performed under such conditions, polyamide is hardly decomposed and polyamide (A) having little deterioration. Is obtained.

Also, the terminal amino group content ([NH _2]) is also by combining a plurality of different kinds of polyamides, it may be polyamide (A) having a terminal amino group content of the desired ([NH _2]). At this time, even if the polyamide (A) contains a polyamide in which only the definition of the terminal amino group content ([NH ₂ ]) does not satisfy the specification of the present invention, the terminal amino group content ([NH ₂ ]) can be used in the present invention as long as the definition of ₂ )) is satisfied. When a plurality of types of polyamides are used in combination, the plurality of types of polyamides may be premixed before being melt kneaded with the modified resin (B) and the conductive filler (C). May be used.

The terminal amino group content ([NH ₂ ]) as used herein refers to the amount of terminal amino groups (unit: μmol) contained in 1 g of the polyamide (A), and is based on the neutralization titration method using an indicator. Can be sought.

Examples of the unsaturated compound having a carboxyl group in the modified resin (B) modified with the unsaturated compound having a carboxyl group and / or an acid anhydride group include acrylic acid, methacrylic acid, maleic acid, fumaric acid, and itaconic acid. And α, β-unsaturated carboxylic acids such as Examples of the unsaturated compound having an acid anhydride group include dicarboxylic anhydrides having an α, β-unsaturated bond such as maleic anhydride and itaconic anhydride. The unsaturated compound having a carboxyl group and / or an acid anhydride group is preferably a dicarboxylic acid anhydride having an α, β-unsaturated bond, and more preferably maleic anhydride.

The content of carboxyl group and acid anhydride group in the modified resin (B) is preferably in the range of 25 to 200 μmol / g, more preferably in the range of 50 to 100 μmol / g. When the content of the functional group is less than 25 μmol / g, the impact resistance improving effect may not be sufficient. On the other hand, when the content exceeds 200 μmol / g, the resulting polyamide resin composition The fluidity of the resin may decrease, and the moldability may decrease.

Examples of the base (unmodified) resin in the modified resin (B) modified with an unsaturated compound having a carboxyl group and / or an acid anhydride group used in the present invention include low density polyethylene and medium density. Polyethylene, high density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-propylene-diene copolymer, ethylene-vinyl acetate copolymer, saponified ethylene-vinyl acetate copolymer, ethylene -Polyolefin resins such as acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl acrylate copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl acrylate copolymer, polybutadiene; styrene -Ethylene copolymer, styrene-propylene copolymer Styrene resins such as polymers, styrene-butene copolymers, styrene-propylene-diene copolymers; polyacrylonitrile, polymethacrylonitrile, acrylonitrile-styrene copolymers, acrylonitrile-butadiene-styrene copolymers, methacrylonitrile -Polynitrile resins such as butadiene-styrene copolymers; Polymethacrylate resins such as polymethyl methacrylate and polyethyl methacrylate; Polyvinyl ester resins such as polyvinyl acetate; Polyvinylidene chloride, polyvinyl chloride, vinyl chloride- Polyvinyl chloride resins such as vinylidene chloride copolymer and vinylidene chloride-methyl acrylate copolymer; polyvinylidene fluoride, polyvinyl fluoride, ethylene-tetrafluoroethylene copolymer, polychlorotrifluoroethylene, Styrene - chlorotrifluoroethylene copolymer, tetrafluoroethylene - hexafluoropropylene copolymer, tetrafluoroethylene - hexafluoropropylene - vinylidene fluoride copolymer, fluorine resin and the like. These resins may be used alone or in combination of two or more. As the modified resin (B) modified with an unsaturated compound having a carboxyl group and / or an acid anhydride group, the impact resistance, mechanical properties and heat resistance of the resulting molded product are further improved. Preferably, at least one resin selected from the group consisting of a resin based on resin, a styrene resin, a polynitrile resin, and a fluorine resin is modified with an unsaturated compound having a carboxyl group and / or an acid anhydride group. , Low density polyethylene, medium density polyethylene, high density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-propylene-diene copolymer, acrylonitrile-butadiene-styrene copolymer, polyvinylidene fluoride , And ethylene-tetrafluoroethylene More preferably those modified by an unsaturated compound having a carboxyl group and / or acid anhydride groups at least one selected from the group consisting of down copolymer.

As a modification method using an unsaturated compound having a carboxyl group and / or an acid anhydride group, the above resin is copolymerized with an unsaturated compound having a carboxyl group and / or an acid anhydride group when the resin is produced by addition polymerization. And a method in which an unsaturated compound having a carboxyl group and / or an acid anhydride group is grafted to the above resin. The modified resin (B) is preferably modified by graft-reacting the above resin with an unsaturated compound having a carboxyl group and / or an acid anhydride group.

Examples of the conductive filler (C) used in the present invention include granular, flaky and fibrous fillers that impart conductivity to the resin. Examples thereof include carbon fiber, conductive carbon black, carbon nanotube, metal fiber, metal powder, metal flake, metal oxide powder, and metal-coated fiber. Among these, at least one selected from the group consisting of carbon fiber, conductive carbon black, and carbon nanotube is preferable because of its low specific gravity and excellent balance between the conductivity imparting effect and the reinforcing effect.

The above-mentioned carbon fiber may be either pitch-based or PAN-based carbon fiber, but PAN-based carbon fiber is more preferable in terms of elastic modulus and impact resistance. The average fiber length of the carbon fibers is preferably in the range of 10 μm to 10 mm in the state after melt-kneading from the viewpoint of maintaining good moldability and improving the mechanical properties and heat resistance of the obtained molded product. The thickness is more preferably in the range of 50 μm to 5 mm, and still more preferably in the range of 100 μm to 2 mm. The aspect ratio of the carbon fiber is preferably in the range of 1 to 3000, and more preferably in the range of 10 to 500.

As the conductive carbon black, commercially available conductive carbon black can be used. For example, Ketjen Black EC600JD and EC300J available from Ketjen Black International Co., Ltd .; Vulcan available from Cabot Corporation XC-72, XC-305; Printex XE2B available from Degussa, # 5500, # 4500 available from Tokai Carbon Co., Ltd., # 5400B available from Mitsubishi Chemical Corporation, and the like.

The carbon nanotubes may have a single-layer structure or a multilayer structure. A carbon material partially having a carbon nanotube structure can also be used. Further, the carbon nanotube is not limited to a cylindrical shape, and may have a coiled shape in which a spiral makes a round at a pitch of 1 μm or less. Carbon nanotubes are commercially available. For example, BAYTUBES C 150 P (manufactured by Bayer MaterialScience), NANOCYL NC7000 (manufactured by Nanosil), VGCF-X (manufactured by Showa Denko KK), Hyperion Catalysis International BN fibrils available from the company. In addition to the name of carbon nanotube, it may be called graphite fibril, carbon fibril, or the like. The diameter of the carbon nanotube is preferably 0.5 to 100 nm, more preferably 1 to 30 nm. If the diameter of the carbon nanotube is less than 0.5 nm, the dispersibility tends to deteriorate, and the conductivity may be lowered. On the other hand, if the diameter is larger than 100 nm, the appearance of the molded product tends to deteriorate, and the conductivity may be lowered. The aspect ratio of the carbon nanotube is preferably 5 or more. If the aspect is less than 5, the conductivity may be lowered.

If necessary, the polyamide resin composition of the present invention may be made of a resin other than the polyamide (A) and the modified resin (B), a filler other than the conductive filler (C), a crystal nucleating agent, heat, light or Other components such as a stabilizer against oxygen, a copper-based stabilizer, a colorant, an antistatic agent, a plasticizer, a lubricant, a flame retardant, and a flame retardant aid may be included.

Examples of other resins include low density polyethylene, medium density polyethylene, high density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-propylene-diene copolymer, and ethylene-vinyl acetate copolymer. Polymer, saponified ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl acrylate copolymer, ethylene-methyl methacrylate copolymer, ethylene-acrylic Polyolefin resins such as ethyl acid copolymer and polybutadiene; Polyester resins such as polybutylene terephthalate, polyethylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, polyarylate, and liquid crystalline polyester Polyether resins such as polyacetal and polyphenylene oxide; Polysulfone resins such as polysulfone and polyethersulfone; Polythioether resins such as polyphenylene sulfide and polythioethersulfone; Polyketone resins such as polyetheretherketone and polyallyletherketone; Styrene Styrene resins such as ethylene copolymers, styrene-propylene copolymers, styrene-butene copolymers, styrene-propylene-diene copolymers; polyacrylonitrile, polymethacrylonitrile, acrylonitrile-styrene copolymers, acrylonitrile- Polynitrile resins such as butadiene-styrene copolymer, methacrylonitrile-butadiene-styrene copolymer; poly, such as polymethyl methacrylate and polyethyl methacrylate Tacrylate resins; polyvinyl ester resins such as polyvinyl acetate; polyvinyl chloride resins such as polyvinylidene chloride, polyvinyl chloride, vinyl chloride-vinylidene chloride copolymer, vinylidene chloride-methyl acrylate copolymer; cellulose acetate, Cellulose-based resins such as cellulose butyrate; polyvinylidene fluoride, polyvinyl fluoride, ethylene-tetrafluoroethylene copolymer, polychlorotrifluoroethylene, ethylene-chlorotrifluoroethylene copolymer, tetrafluoroethylene-hexafluoropropylene copolymer Fluorine resin such as polymer, tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymer; polycarbonate resin; polyimide such as thermoplastic polyimide, polyamideimide, polyetherimide Resin, thermoplastic polyurethane resin; polyamide 6, polyamide 66, polyamide 46, polyamide 6,10, polyamide 6,12, polyamide 11, polyamide 12, polymetaxylylene adipamide (MXD6), polypentamethylene terephthalamide, Examples thereof include polybis (4-aminocyclohexyl) methane dodecamide (PACM12) and polyamide resins (except for polyamide (A)) using one or more of these polyimide raw diamines and raw dicarboxylic acids. .

Other fillers include, for example, fibrous fillers such as glass fibers, calcium carbonate, wollastonite, silica, silica alumina, alumina, titanium dioxide, potassium titanate, magnesium hydroxide, molybdenum disulfide, etc. Fillers; Flaky fillers such as hydrotalcite, glass flakes, mica, clay, montmorillonite, kaolin and the like.

The crystal nucleating agent is not particularly limited as long as it is generally used as a crystal nucleating agent for polyamide resin. For example, talc, calcium stearate, aluminum stearate, barium stearate, zinc stearate, antimony oxide, Examples thereof include magnesium oxide and any mixture thereof. Among these, talc is preferable because it has a great effect of increasing the crystallization speed of the polyamide resin. The crystal nucleating agent may be treated with a silane coupling agent, a titanium coupling agent or the like for the purpose of improving compatibility with the polyamide resin.

The stabilizer against heat, light or oxygen is not particularly limited as long as it is generally used as a stabilizer for polyamide resins. For example, hindered phenol compounds, hindered amine compounds, phenylenediamine compounds , Phenolic compounds, benzotriazole compounds, benzophenone compounds, phenyl salicylate compounds, epoxy compounds, phosphite compounds, phosphonite compounds, phosphorus compounds, thio compounds, thioether compounds, tin compounds, metal halides, etc. It is done. Preferably, a halide (eg, chloride, bromide, iodide) of a Group I metal (eg, sodium, potassium, lithium), copper (I) halide (eg, copper (I) chloride), A combination of copper bromide (I), copper iodide (I)), a group I metal halide and a copper (I) halide, with copper (I) halide being more preferred.

The plasticizer is not particularly limited as long as it is generally used as a plasticizer for polyamide resins. For example, benzenesulfonic acid alkylamide compounds, toluenesulfonic acid alkylamide compounds, hydroxybenzoic acid alkylester compounds Compounds and the like.

The lubricant is not particularly limited as long as it is generally used as a lubricant for polyamide resins. For example, higher fatty acid compounds, oxy fatty acid compounds, fatty acid amide compounds, alkylene bis fatty acid amide compounds, fatty acid lower compounds. Examples include alcohol ester compounds and metal soap compounds. Fatty acid amide compounds such as stearic acid amide, palmitic acid amide, methylene bisstearamide, ethylene bisstearamide and the like are preferable because they are excellent in external lubricity effect.

The content of these other components in the polyamide resin composition is preferably 50% by mass or less, more preferably 20% by mass or less, and further preferably 5% by mass or less.

The polyamide resin composition of the present invention comprises the above polyamide (A), a modified resin (B) modified with an unsaturated compound having a carboxyl group and / or an acid anhydride group, a conductive filler (C), and, if necessary. And other ingredients as described above. Polyamide (A), modified resin (B) and conductive filler (C) are used in a proportion of 100 parts by mass of polyamide (A), modified resin (B) and conductive filler (C). 40 to 96.5 parts by mass, modified resin (B) 3 to 30 parts by mass, conductive filler (C) 0.5 to 30 parts by mass, polyamide (A) 60 to 94.5 parts by mass, The modified resin (B) is preferably 5 to 20 parts by mass, the conductive filler (C) is preferably 0.5 to 20 parts by mass, the polyamide (A) is 65 to 94 parts by mass, and the modified resin (B) is 5 to 20 parts by mass. More preferably, 20 parts by mass and the conductive filler (C) is 1 to 15 parts by mass.

In the polyamide resin composition of the present invention, the terminal amino group of the polyamide (A) reacts with the carboxyl group and / or the acid anhydride group of the modified resin (B), whereby (A) phase and (B ) The affinity of the interface with the phase is increased, and impact resistance and tensile elongation at break are improved. However, if the reaction is insufficient, the effect of improving impact resistance or the like cannot be obtained, and if the reaction is excessive, the melt viscosity exceeds the appropriate range. Therefore, in the polyamide resin composition of the present invention, the number of moles (M _I ) of the terminal amino group of the polyamide (A) in the total 1 g of the polyamide (A) and the modified resin (B), and the modified resin (B) The difference (M _I -M _II ) from the number of moles (M _II ) of the carboxyl group and the acid anhydride group of M is -5.0 μmol or more and less than 4.0 μmol, and M _II is 4.0 μmol It needs to be bigger. When the difference (M _I −M _II ) is outside the above range, the melt viscosity is increased or the viscosity is increased by heating. When M _II is 4.0 μmol or less, the impact resistance is decreased. . The difference (M _I −M _II ) is preferably −5.0 μmol or more and 2.0 μmol or less from the viewpoint of making the melt viscosity within an appropriate range and improving impact resistance and moldability. More preferably, it is 0 mol or more and 1.0 μmol or less.

The number of moles of the terminal amino group of the polyamide (A) and the number of moles of the carboxyl group and acid anhydride group of the modified resin (B) in a total of 1 g of the polyamide (A) and the modified resin (B) are as follows: The number of moles of terminal amino group of polyamide (A) per gram and the number of moles of carboxyl group and acid anhydride group of modified resin (B) per gram are determined by neutralization titration using an indicator, respectively. It can be calculated by using the weight ratio of the polyamide (A) and the modified resin (B).

The polyamide resin composition of the present invention is prepared by mixing the polyamide (A), the modified resin (B), the conductive filler (C), and, if necessary, the above other components by a known method such as melt kneading. can do. As the melt-kneading method, conventionally known melt-kneading methods can be employed, and for example, it can be carried out using a kneader such as a single-screw extruder, a twin-screw extruder, a kneader, or a Banbury mixer. There are no particular limitations on the type of apparatus and melt-kneading conditions used at that time. For example, the polyamide resin composition of the present invention is obtained by kneading at a temperature in the range of about 280 to 350 ° C. for 1 to 30 minutes. be able to. In the present specification, the melt kneading means kneading performed under a condition that at least the polyamide (A) melts.

When the polyamide resin composition of the present invention is obtained by melt-kneading, the polyamide (A) and the modified resin (B) are melt-kneaded in an extruder or the like, and the conductive filler (C) is mixed in the extruder or the like. Side feed from the downstream supply port is preferred because a polyamide resin composition having better mechanical properties can be obtained.

Further, using the same-direction rotating twin-screw extruder (a) having at least one upstream supply port and one downstream supply port, the polyamide (A), the modified resin (B), and the conductive filler (C) are added. A method of kneading in advance and pouring them into the upstream supply port and melting and kneading them [kneading method A], a part or all of the polyamide (A) melt and conductive filler (C) are mixed in advance to prepare a master batch. The master batch, the remainder of the polyamide (A), and the modified resin (B) are mixed, put into the upstream supply port of the same-direction rotating twin-screw extruder (a), and melt-kneaded. Method [kneading method B], polyamide (A) and conductive filler (C) are mixed in advance, charged into the upstream supply port of the same-direction rotating twin-screw extruder (a), melt-kneaded, and supplied downstream A method in which the modified resin (B) is introduced from the mouth and melt-kneaded. [Kneading method C], preparing a masterbatch by previously mixing a part or all of the polyamide (A) melt and a conductive material, mixing the masterbatch and the remainder of the polyamide (A), A method of kneading by introducing into the upstream supply port of the above-mentioned co-rotating twin-screw extruder (a) and melt-kneading, and introducing a modified resin (B) from the downstream supply port [kneading method D], polyamide ( A part or all of A) and the modified resin (B) are mixed in advance, charged into the upstream supply port of the co-rotating twin screw extruder (a), melt-kneaded, and the conductive filler from the downstream supply port. A method [kneading method E] in which (C) and the remainder of polyamide (A) are added and melt-kneaded can be preferably employed.

The polyamide resin composition of the present invention has an appropriate melt viscosity, excellent moldability, electrical conductivity, toughness such as impact resistance and elongation, and mechanical strength such as tensile strength. It is excellent in both characteristics of the characteristics at the same time, and also excellent in characteristics such as fuel barrier properties, heat resistance, low water absorption, chemical resistance, and long-term heat resistance. Therefore, the molded article containing the polyamide resin composition of the present invention is useful for various applications.

Molding of the polyamide resin composition of the present invention can be carried out according to thermoplastic molding such as injection molding, extrusion molding, press molding, blow molding, calendar molding, casting molding, etc. It can be performed by a molding method generally used for the combined composition. A molding method combining the above molding methods can also be employed. Furthermore, the polyamide resin composition of the present invention and other polymers can be composite-molded.

Favorable uses for molded articles containing the polyamide resin composition of the present invention are fuel system parts such as fuel caps, fuel tanks, fuel sender modules, fuel cut-off valves, canisters, and fuel pipes. The fuel system parts can be used for various devices including engines such as gasoline, light oil and the like, such as automobiles, tractors, cultivators, mowers, lawn mowers, and chainsaws.

As the fuel system component, a fuel pipe is preferable because of its characteristics. The fuel pipe can be particularly suitably used as an automobile fuel pipe. Examples of the fuel piping for automobiles include a fuel filler tube, a fuel delivery pipe, a fuel filler neck, a quick connector, and the like.

The fuel pipe can be obtained by extruding into a hose shape, for example. The layer structure is a fuel pipe in which the polyamide resin composition of the present invention is molded as a single layer, or a fuel pipe having a multilayer structure of two or more layers, and one or more layers are the polyamide resin composition of the present invention. Preferably, the fuel pipe has a multilayer structure of two or more layers using the polyamide resin composition of the present invention as the innermost layer. When the fuel pipe has a multilayer structure, the other layers may be other resin composition layers, rubber layers, reinforcing yarn layers, and the like.

Specific examples of materials constituting the other layers of the fuel pipe include, for example, polyester resins such as polybutylene terephthalate, polyethylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, and polyethylene isophthalate; ethylene-tetrafluoroethylene copolymer Fluorine resins such as polymers, polychlorotrifluoroethylene, ethylene-chlorotrifluoroethylene copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymer; polyethylene Polyolefin resin such as polypropylene and polystyrene; saponified ethylene-vinyl acetate copolymer, polyacetal, polyphenylene sulfide; polyamide 6, polyamido 66, polyamide 46, polyamide 610, polyamide 612, polyamide 11, polyamide 12, polyamide 6T, polyamide 9T, polyamide 10T, polyamide 6T / polyamide 11 copolymer, polyamide 6T / polyamide 12 copolymer, polyamide 6T / polyamide 66 Polymer, polyamide 6T / polyamide 6I copolymer, polyamide 6T / polyamide 6I / polyamide 66 copolymer, hexamethylenediamine / 2-methyl-1,5-pentamethylenediamine / terephthalic acid copolymer, polymetaxylylene aziene Pamide (MXD6), polypentamethylene terephthalamide, and polyamide resins using one or more of these polyamide raw material diamines and raw dicarboxylic acids.

The molded product containing the polyamide resin composition of the present invention includes, for example, a radiator grill, a rear spoiler, a wheel cover, a wheel cap, a cowl vent grill, an air outlet louver, an air scoop, a hood bulge, a fender, a back door, and the like. Automotive exterior parts: cylinder head cover, engine mount, air intake manifold, throttle body, air intake pipe, radiator tank, radiator support, water pump inlet, water pump outlet, thermostat housing, cooling fan, fan shroud , Oil pan, oil filter housing, oil filler cap, oil level gauge, timing belt, timing belt cover, air Automotive engine compartment parts such as gin covers; automotive drive system parts such as shift lever housings and propeller shafts; automotive chassis parts such as stabilizer bars and linkage rods; window regulators, door locks, door handles, outs Functional parts for automobiles such as side door mirror stays, accelerator pedals, pedal modules, seal rings, bearings, bearing retainers, gears, actuators; wire harnesses / connectors, relay blocks, sensor housings, encapsulations, ignition coils, It can also be used in applications such as automotive electronic parts such as distributors and caps; electrical and electronic parts such as connectors and LED reflectors.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Terminal amino group content ([NH ₂ ]), carboxyl group and acid anhydride group content, production method of molded article (test piece), conductivity, impact resistance, melt viscosity and its change, and fuel barrier properties The evaluation method is shown below.

(1) Measurement of terminal amino group content ([NH ₂ ]) of polyamide (A) and content of carboxyl group and acid anhydride group of modified resin (B) 1 g of polyamide (A) was dissolved in 35 mL of phenol, A sample solution was prepared by mixing 2 mL of methanol. Timol blue was used as an indicator, and titration was performed using 0.01 N aqueous HCl, and the terminal amino group content ([NH ₂ ], unit: μmol / g) was measured. Further, the content of the carboxyl group and the acid anhydride group of the modified resin (B) was determined using a sample solution prepared by dissolving 5 g of the pellet of the modified resin (B) in 170 mL of toluene and further adding 30 mL of ethanol. It was determined by neutralization titration with 0.1 N KOH ethanol solution using phenolphthalein as an indicator.

(2) Production of molded product (test piece) Using an injection molding machine (clamping force: 80 tons, screw diameter: φ32 mm) manufactured by Toshiba Machine Co., Ltd., a cylinder temperature of 320 ° C. and a mold temperature of 150 ° C. Below, the polyamide resin composition was shape | molded using the T runner metal mold | die or the double T runner metal mold | die, and the test piece was produced.

(3) Conductivity evaluation Using the test piece prepared by the above method, a test was performed at an applied voltage of 90 V using a low resistivity meter (Loresta-GP, manufactured by Mitsubishi Chemical Corporation) according to ASTM D257. The surface resistivity at one point in the center of the piece was measured. The measurement was performed using five different test pieces, and the conductivity was evaluated using the addition average value as the surface resistivity (average value).

(4) Evaluation of impact resistance At 23 ° C. and −40 ° C. using an Izod impact tester (manufactured by Toyo Seiki Seisakusyo Co., Ltd.) according to ASTM D256 using the test piece prepared by the above method. Impact resistance was evaluated by measuring notched Izod impact values.

(5) Evaluation of melt viscosity Using a capillograph (manufactured by Toyo Seiki Seisakusho Co., Ltd.), the melt viscosity of the polyamide resin composition was measured under the conditions of a measurement temperature of 310 ° C, a melting time of 4 minutes, and a shear rate of 122 s- ¹ .

(6) Evaluation of change in melt viscosity Using a melt indexer (manufactured by Toyo Seiki Seisakusho Co., Ltd.), the MFR of the polyamide resin composition under the conditions of a measurement temperature of 310 ° C., a load of 5 kg, a melting time of 4 minutes, and a melting time of 15 minutes. Values were measured and compared. In Tables 3 and 4, the case where the MFR value of the melting time of 15 minutes is larger than the MFR value of the melting time of 4 minutes is positive (+), and the case where the MFR value is small is negative (-).

(7) Fuel barrier property Using a polyamide resin composition, a film having a diameter of 100 mm and a thickness of 150 μm is prepared, and fuel permeation is conducted at 40 ° C. and 65 RH% using a liquid permeability measuring device (manufactured by GTR Tech Co., Ltd.). The coefficient was measured. As a measurement solvent, a simulated fuel of isooctane / ethanol / toluene = 45/10/45 (volume ratio) was used.

[Reference Example 1] Production of semi-aromatic polyamide (PA9T-1) 9922.1 g (59.73 mol) of terephthalic acid, a mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine [former / latter = 50/50 (molar ratio)] 9497.4 g (60.00 mol), 67.2 g (0.55 mol) of benzoic acid, 19.5 g of sodium hypophosphite monohydrate (based on the total mass of the raw materials) 0.1 mass%) and 5 liters of distilled water were placed in an autoclave having an internal volume of 40 liters and purged with nitrogen. The mixture was stirred at 100 ° C. for 30 minutes, and the temperature inside the autoclave was increased to 220 ° C. over 2 hours. At this time, the pressure inside the autoclave was increased to 2 MPa. The reaction was continued as it was for 2 hours, then the temperature was raised to 230 ° C., and then the temperature was maintained at 230 ° C. for 2 hours, and the reaction was carried out while gradually removing water vapor and keeping the pressure at 2 MPa. Next, the pressure was reduced to 1 MPa over 30 minutes, and the reaction was further continued for 1 hour to obtain a prepolymer having an intrinsic viscosity [η] of 0.16 dl / g. This was dried at 100 ° C. under reduced pressure for 12 hours and pulverized to a particle size of 2 mm or less. This was solid-phase polymerized at 230 ° C. and 13 Pa (0.1 mmHg) for 10 hours. The melting point was 265 ° C., the intrinsic viscosity [η] was 1.60 dl / g, and the terminal amino group content ([NH ₂ ]) was 3 μmol. A white polyamide having a terminal carboxyl group content of 65 μmol / g and a terminal blocking rate of 30% was obtained. This polyamide is abbreviated as “PA9T-1.”

[Reference Example 2] Production of semiaromatic polyamide (PA9T-2) 9947.9 g (59.88 mol) of terephthalic acid, mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine [former / latter = 50/50 (molar ratio)] 9744.8 g (61.50 mol), benzoic acid 29.3 g (0.24 mol), sodium hypophosphite monohydrate 19.7 g (based on the total mass of the raw materials) 0.1 mass%) and 5 liters of distilled water were placed in an autoclave having an internal volume of 40 liters and purged with nitrogen. The mixture was stirred at 100 ° C. for 30 minutes, and the temperature inside the autoclave was increased to 220 ° C. over 2 hours. At this time, the pressure inside the autoclave was increased to 2 MPa. The reaction was continued as it was for 2 hours, then the temperature was raised to 230 ° C., and then the temperature was maintained at 230 ° C. for 2 hours, and the reaction was carried out while gradually removing water vapor and keeping the pressure at 2 MPa. Next, the pressure was reduced to 1 MPa over 30 minutes, and the reaction was further continued for 1 hour to obtain a prepolymer having an intrinsic viscosity [η] of 0.14 dl / g. This was dried at 100 ° C. under reduced pressure for 12 hours and pulverized to a particle size of 2 mm or less. This was solid-phase polymerized at 230 ° C. and 13 Pa (0.1 mmHg) for 10 hours. The melting point was 256 ° C., the intrinsic viscosity [η] was 1.60 dl / g, and the terminal amino group content ([NH ₂ ]) was 80 μmol. A white polyamide having a terminal carboxyl group content of 5 μmol / g and a terminal blocking rate of 12% was obtained. This polyamide is abbreviated as “PA9T-2”.

[Reference Example 3] Production of semi-aromatic polyamide (PA9T-3) 9868.1 g (59.40 mol) of terephthalic acid, a mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine [former / latter = 50/50 (molar ratio)] 9744.8 g (61.50 mol), benzoic acid 146.5 g (1.20 mol), sodium hypophosphite monohydrate 19.7 g (based on the total mass of the raw materials) 0.1 mass%) and 5 liters of distilled water were placed in an autoclave having an internal volume of 40 liters and purged with nitrogen. The mixture was stirred at 100 ° C. for 30 minutes, and the temperature inside the autoclave was increased to 220 ° C. over 2 hours. At this time, the pressure inside the autoclave was increased to 2 MPa. The reaction was continued as it was for 2 hours, then the temperature was raised to 230 ° C., and then the temperature was maintained at 230 ° C. for 2 hours, and the reaction was carried out while gradually removing water vapor and keeping the pressure at 2 MPa. Next, the pressure was reduced to 1 MPa over 30 minutes, and the reaction was further continued for 1 hour to obtain a prepolymer having an intrinsic viscosity [η] of 0.14 dl / g. This was dried at 100 ° C. under reduced pressure for 12 hours and pulverized to a particle size of 2 mm or less. This was solid-phase polymerized at 230 ° C. and 13 Pa (0.1 mmHg) for 10 hours. The melting point was 265 ° C., the intrinsic viscosity [η] was 1.20 dl / g, and the terminal amino group content ([NH ₂ ]) was 80 μmol. A white polyamide having a terminal carboxyl group content of 5 μmol / g and a terminal blocking rate of 42% was obtained. This polyamide is abbreviated as “PA9T-3”.

[Reference Example 4] Production of semi-aromatic polyamide (PA9T-4) 9843.2 g (59.25 mol) of terephthalic acid, mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine [former / latter = 50/50 (molar ratio)] 9497.4 g (60.00 mol), benzoic acid 183.2 g (1.50 mol), sodium hypophosphite monohydrate 19.5 g (based on the total mass of the raw materials) 0.1 mass%) and 5 liters of distilled water were placed in an autoclave having an internal volume of 40 liters and purged with nitrogen. The mixture was stirred at 100 ° C. for 30 minutes, and the temperature inside the autoclave was increased to 220 ° C. over 2 hours. At this time, the pressure inside the autoclave was increased to 2 MPa. The reaction was continued as it was for 2 hours, then the temperature was raised to 230 ° C., and then the temperature was maintained at 230 ° C. for 2 hours, and the reaction was carried out while gradually removing water vapor and keeping the pressure at 2 MPa. Next, the pressure was reduced to 1 MPa over 30 minutes, and the reaction was further continued for 1 hour to obtain a prepolymer having an intrinsic viscosity [η] of 0.16 dl / g. This was dried at 100 ° C. under reduced pressure for 12 hours and pulverized to a particle size of 2 mm or less. This was solid-phase polymerized at 230 ° C. and 13 Pa (0.1 mmHg) for 10 hours. The melting point was 256 ° C., the intrinsic viscosity [η] was 1.20 dl / g, and the terminal amino group content ([NH ₂ ]) was 3 μmol. A white polyamide having a terminal carboxyl group content of 65 μmol / g and a terminal blocking rate of 54% was obtained. This polyamide is abbreviated as “PA9T-4”.

[Reference Example 5] Production of semi-aromatic polyamide (PA9T-5) 9870.6 g (59.42 mol) of terephthalic acid, mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine [former / latter = 50/50 (molar ratio)] 9497.4 g (60.00 mol), benzoic acid 142.9 g (1.17 mol), sodium hypophosphite monohydrate 19.5 g (based on the total mass of the raw materials) 0.1 mass%) and 5 liters of distilled water were placed in an autoclave having an internal volume of 40 liters and purged with nitrogen. The mixture was stirred at 100 ° C. for 30 minutes, and the temperature inside the autoclave was increased to 220 ° C. over 2 hours. At this time, the pressure inside the autoclave was increased to 2 MPa. The reaction was continued as it was for 2 hours, then the temperature was raised to 230 ° C., and then the temperature was maintained at 230 ° C. for 2 hours, and the reaction was carried out while gradually removing water vapor and keeping the pressure at 2 MPa. Next, the pressure was reduced to 1 MPa over 30 minutes, and the reaction was further continued for 1 hour to obtain a prepolymer having an intrinsic viscosity [η] of 0.16 dl / g. This was dried at 100 ° C. under reduced pressure for 12 hours and pulverized to a particle size of 2 mm or less. This was solid-phase polymerized at 230 ° C. and 13 Pa (0.1 mmHg) for 10 hours. The melting point was 265 ° C., the intrinsic viscosity [η] was 1.30 dl / g, and the terminal amino group content ([NH ₂ ]) was 10 μmol. A white polyamide having a terminal carboxyl group content of 60 μmol / g and a terminal blocking ratio of 46% was obtained. This polyamide is abbreviated as “PA9T-5”.

[Reference Example 6] Production of semi-aromatic polyamide (PA6T) 9983.1 g (59.49 mol) of terephthalic acid, a mixture of 1,6-hexanediamine and 2-methyl-1,5-pentanediamine [former / latter = 50/50 (molar ratio)] 6792.6 g (60.00 mol), benzoic acid 124.6 g (1.02 mol), sodium hypophosphite monohydrate 17.0 g (based on the total mass of the raw materials) 0.1 mass%) and 5 liters of distilled water were placed in an autoclave having an internal volume of 40 liters and purged with nitrogen. The mixture was stirred at 100 ° C. for 30 minutes, and the temperature inside the autoclave was increased to 220 ° C. over 2 hours. At this time, the pressure inside the autoclave was increased to 2 MPa. The reaction was continued as it was for 2 hours, then the temperature was raised to 230 ° C., and then the temperature was maintained at 230 ° C. for 2 hours, and the reaction was carried out while gradually removing water vapor and keeping the pressure at 2 MPa. Next, the pressure was reduced to 1 MPa over 30 minutes, and the reaction was further continued for 1 hour to obtain a prepolymer having an intrinsic viscosity [η] of 0.16 dl / g. This was dried at 100 ° C. under reduced pressure for 12 hours and pulverized to a particle size of 2 mm or less. This was solid-phase polymerized at 230 ° C. and 13 Pa (0.1 mmHg) for 10 hours. The melting point was 315 ° C., the intrinsic viscosity [η] was 1.30 dl / g, and the terminal amino group content ([NH ₂ ]) was 10 μmol. A white polyamide having a terminal carboxyl group content of 59 μmol / g and a terminal blocking rate of 47% was obtained. This polyamide is abbreviated as “PA6T”.

[Reference Example 7] Production of semi-aromatic polyamide (PA10T) 9861.5 g (59.36 mol) of terephthalic acid, 10339.2 g (60.00 mol) of 1,10-decanediamine, 156.3 g of benzoic acid (1. 28 mol), 20.4 g of sodium hypophosphite monohydrate (0.1% by mass with respect to the total mass of the raw material) and 5 liters of distilled water were placed in an autoclave having an internal volume of 40 liters and purged with nitrogen. The mixture was stirred at 100 ° C. for 30 minutes, and the temperature inside the autoclave was increased to 220 ° C. over 2 hours. At this time, the pressure inside the autoclave was increased to 2 MPa. The reaction was continued as it was for 2 hours, then the temperature was raised to 230 ° C., and then the temperature was maintained at 230 ° C. for 2 hours, and the reaction was carried out while gradually removing water vapor and keeping the pressure at 2 MPa. Next, the pressure was reduced to 1 MPa over 30 minutes, and the reaction was further continued for 1 hour to obtain a prepolymer having an intrinsic viscosity [η] of 0.16 dl / g. This was dried at 100 ° C. under reduced pressure for 12 hours and pulverized to a particle size of 2 mm or less. This was solid-phase polymerized at 230 ° C. and 13 Pa (0.1 mmHg) for 10 hours. The melting point was 318 ° C., the intrinsic viscosity [η] was 1.30 dl / g, and the terminal amino group content ([NH ₂ ]) was 10 μmol. A white polyamide having a terminal carboxyl group content of 58 μmol / g and a terminal blocking rate of 48% was obtained. This polyamide is abbreviated as “PA10T”.

[Reference Example 8] Production of semiaromatic polyamide (PA9N) 2.6-Naphthalenedicarboxylic acid 1283.3 g (59.32 mol), mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine [ Former / latter = 50/50 (molar ratio)] 9497.4 g (60.00 mol), benzoic acid 167.3 g (1.37 mol), sodium hypophosphite monohydrate 22.5 g (total of raw materials 0.1 mass% with respect to mass) and 5 liters of distilled water were put into an autoclave having an internal volume of 40 liters, and the atmosphere was replaced with nitrogen. The mixture was stirred at 100 ° C. for 30 minutes, and the temperature inside the autoclave was increased to 220 ° C. over 2 hours. At this time, the pressure inside the autoclave was increased to 2 MPa. The reaction was continued as it was for 2 hours, then the temperature was raised to 230 ° C., and then the temperature was maintained at 230 ° C. for 2 hours, and the reaction was carried out while gradually removing water vapor and keeping the pressure at 2 MPa. Next, the pressure was reduced to 1 MPa over 30 minutes, and the reaction was further continued for 1 hour to obtain a prepolymer having an intrinsic viscosity [η] of 0.16 dl / g. This was dried at 100 ° C. under reduced pressure for 12 hours and pulverized to a particle size of 2 mm or less. This was solid-phase polymerized at 230 ° C. and 13 Pa (0.1 mmHg) for 10 hours. The melting point was 275 ° C., the intrinsic viscosity [η] was 1.30 dl / g, and the terminal amino group content ([NH ₂ ]) was 10 μmol. White polyamide having a terminal carboxyl group content of 58 μmol / g and a terminal blocking ratio of 46% was obtained. This polyamide is abbreviated as “PA9N”.

In the following examples and comparative examples, the following polyamide (A), modified resin (B) and conductive filler (C) were used.

Polyamide (A)
PA9T-1 to PA9T-5 produced in Reference Examples 1 to 8 above, and PA6T, PA10T, and PA9N were used as they were, or were used together in the proportions shown in Table 1 below.

Modified resin (B)
EBR-1: Maleic anhydride modified ethylene-butene copolymer (“Tafmer MH7020” manufactured by Mitsui Chemicals, content of acid anhydride group: 100 μmol / g)
EBR-2: Maleic anhydride modified ethylene-butene copolymer (“Tafmer MH7010” manufactured by Mitsui Chemicals, content of acid anhydride group: 50 μmol / g)
EBR-3: Maleic anhydride modified ethylene-butene copolymer (“Tafmer MH7007” manufactured by Mitsui Chemicals, content of acid anhydride group: 25 μmol / g)
EBR-4: Maleic anhydride modified ethylene-butene copolymer (“Tafmer MH5010” manufactured by Mitsui Chemicals, content of acid anhydride group: 50 μmol / g)

Conductive filler (C)
CB: Carbon black ("KB EC600JD" manufactured by Ketjen Black International)
CNT: carbon nanotube (“VGCF-X” manufactured by Showa Denko KK, diameter 10-15 nm, fiber length 3 μm, aspect ratio 200-300)

<Examples 1 to 12 and Comparative Examples 1 to 9>
Polyamide (A), modified resin (B) and conductive filler (C) were mixed in advance in the proportions shown in Tables 1 and 2 below, and a twin-screw extruder (“BTN-32” manufactured by Plastic Engineering Laboratory Co., Ltd.) A method of batch feeding into the upstream supply port (top batch method), or a mixture of polyamide (A) and conductive filler (C) in advance, and feeding into the upstream feed port of the above twin screw extruder to melt kneading Then, a modified polyamide resin (B) is introduced from the downstream supply port (elastomer side feed method), melt-kneaded under conditions of a cylinder temperature of 320 to 340 ° C., extruded, cooled and cut to form a pellet-like polyamide resin A composition was prepared. Various physical property evaluations were performed using the obtained polyamide resin composition. The results are shown in Tables 3 and 4 below.

From Table 3, the polyamide resin compositions of Examples 1 to 12 having each requirement defined in the present invention are excellent in conductivity, impact resistance, fuel barrier property and fluidity, and have a negative change in melt viscosity. I understand that.

The polyamide resin compositions obtained in Comparative Examples 1 to 3 and Comparative Examples 6 to 8 had a positive change in melt viscosity because the difference (M _I -M _II ) was too large.

The polyamide resin composition obtained in Comparative Example 4 had a high melt viscosity because the difference (M _I -M _II ) was too small.

Polyamide resin composition obtained in Comparative Example 5, since M _II is low, the impact resistance was inferior.

Since the polyamide resin composition obtained in Comparative Example 9 does not contain a conductive filler (C), the conductivity was remarkably inferior.

The polyamide resin composition of the present invention is excellent in electrical conductivity, impact resistance, melt viscosity stability and moldability, and also has excellent fuel barrier properties, so that it can be used as a material for various molded products including fuel pipes. Useful.

Claims

A terminal amino group comprising a dicarboxylic acid unit containing 50 to 100 mol% of a terephthalic acid unit and / or a naphthalenedicarboxylic acid unit and a diamine unit containing 60 to 100 mol% of an aliphatic diamine unit having 4 to 18 carbon atoms A polyamide (A) having a content ([NH 2 ]) of 5 to 60 μmol / g,
A polyamide resin composition containing a modified resin (B) modified with an unsaturated compound having a carboxyl group and / or an acid anhydride group, and a conductive filler (C),
40 to 96.5 parts by mass of the polyamide (A) and the modified resin (B) with respect to 100 parts by mass in total of the polyamide (A), the modified resin (B), and the conductive filler (C). 3 to 30 parts by mass, 0.5 to 30 parts by mass of the conductive filler (C), and the terminal amino group of the polyamide (A) in a total of 1 g of the polyamide (A) and the modified resin (B) the number of moles and (M I), the modified resin (B) the number of moles of carboxyl groups and acid anhydride groups of the difference between the (M II) (M I -M II) is, -5.0Myu mol 4 A polyamide resin composition having a molecular weight of less than 0.0 μmol and an M II of greater than 4.0 μmol.
2. The polyamide resin composition according to claim 1, wherein the aliphatic diamine unit having 4 to 18 carbon atoms is a 1,9-nonanediamine unit and / or a 2-methyl-1,8-octanediamine unit.
Unsaturated compound in which the modified resin (B) has at least one resin selected from the group consisting of polyolefin resins, styrene resins, polynitrile resins, and fluorine resins, having a carboxyl group and / or an acid anhydride group The polyamide resin composition according to claim 1, which has been modified by:
The polyamide resin composition according to claim 1, wherein the conductive filler (C) is at least one selected from the group consisting of carbon fibers, conductive carbon black, and carbon nanotubes.
The polyamide resin composition according to claim 4, wherein the carbon nanotube has a diameter of 0.5 nm to 100 nm and an aspect ratio of 5 or more.
A molded article comprising the polyamide resin composition according to claim 1.
A fuel pipe including a layer containing the polyamide resin composition according to claim 1.